Summary
web2py remote code execution via hardcoded encryption key in session.connect function
The sample web application in web2py before 2.14.2 might allow remote attackers to execute arbitrary code via vectors involving use of a hardcoded encryption key when calling the session.connect function.
Impact
Credentials are embedded in source code or a binary, making them accessible to anyone who can read the artifact. Typical impact: unauthorized access using the static credential.
CVE-2016-3953 has a CVSS score of 9.8 (Critical). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.14.2); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2016-3953? CVE-2016-3953 is a critical-severity use of hard-coded credentials vulnerability in web2py (pip), affecting versions < 2.14.2. It is fixed in 2.14.2. Credentials are embedded in source code or a binary, making them accessible to anyone who can read the artifact.
- How severe is CVE-2016-3953? CVE-2016-3953 has a CVSS score of 9.8 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of web2py are affected by CVE-2016-3953? web2py (pip) versions < 2.14.2 is affected.
- Is there a fix for CVE-2016-3953? Yes. CVE-2016-3953 is fixed in 2.14.2. Upgrade to this version or later.
- Is CVE-2016-3953 exploitable, and should I be worried? Whether CVE-2016-3953 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2016-3953 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2016-3953? Upgrade
web2pyto 2.14.2 or later.